Police struggling with a San Francisco man who later died in custody used pepper spray on him at least three times -- exceeding manufacturer guidelines to use only a single one-second burst, according to a police memo obtained by The Chronicle.

The internal memo provides the first detailed account of a police struggle with Aaron Williams, a 35-year-old burglary suspect who police said showed phenomenal strength as he wrestled, grabbed for an officer's gun and kept on fighting as several officers sprayed him.

The memo does not mention that manufacturers of the liquid chemical agent, which restricts breathing, recommend the single burst. San Francisco police regulations on pepper spray do not mention how many times it may be used on a resisting suspect.

But police regulations do require that an ambulance be called if anyone sprayed with the liquid chemical has trouble breathing. After Williams was sprayed in front of his flat, he was transported alone in the back of a police van to the Richmond District station, where it was noticed that he was having trouble breathing. He was pronounced dead a few minutes later.

Some witnesses have said Williams was kicked and struck by officers after his hands and legs were bound. Police have said Williams, a cocaine-using parolee whom they suspected of a burglary when they went to his home, kicked and bit as they tried to subdue him.

Reacting to the police memo, an attorney for Williams' family, Bob Kroll, said repeated use of the spray -- which one watchdog group says has been linked to 26 deaths in police incidents in California since 1993 -- clearly contributed to the death.

"We are convinced the combination of the physical assault by police, the pepper-spraying by three officers, the mask they placed over his face which prevented dissipation of the spray, the restraining techniques they used (handcuffs and leg restraints) and his position when he was placed in the police van all contributed to his death," Kroll said.

"He died at the hands of police, period," Kroll said. "Can I be more clear?"

The San Francisco police memo written June 5 by Stephen Zimmerman, the supervising sergeant at the Bush Street scene, gives the most complete police account to date of the incident.

When officers arrived, the memo states, "Williams ran down the stairs toward the officers. The officers' use of verbal persuasion failed to gain the cooperation of the suspect. Williams charged the officers, engaging them physically."

The memo adds: "Williams had his arms around officer (Marc) Andaya, and he tried to get officer Andaya's gun." Since the struggle with Williams, Andaya -- who received a fractured knee and had his thigh bitten -- has been on disability leave and unavailable for comment.

In the wake of Williams' death, it has been revealed that Andaya had several complaints of excessive force against him during his earlier career as an Oakland police officer, and in one case he was suspended by the Oakland force for 30 days.

Andaya was among several of the dozen officers responding to the scene who physically struggled with Williams. "Attempts to use physical control were only minimally effective," the police memo states. "Officer (Kirk) Bozin utilized (pepper spray). The spray appeared to have no effect on Williams except to anger him. . . . Officer Bozin dropped the spray canister. Williams got the spray canister and may have sprayed officer Andaya.

Subsequently, the memo states, officers were able to handcuff Williams. This account differs from that of Joseph Stevens, Williams' 11-year-old nephew, who witnessed the struggle from a second- floor window. He told The Chronicle that police sprayed Williams after he was handcuffed.

Andaya told Sergeant Zimmerman that Williams was a drug user who might be HIV-positive and said he had bit him and was spitting, the memo states. At Andaya's urging, police took a paper mask and put it on Williams, and they also bound his legs after Andaya said "it was imperative" to do so, according to the memo.

The document said Williams, by then handcuffed and in leg restraints, was placed in the patrol wagon on his right side. Police regulations state that the best position for a handcuffed prisoner is sitting upright.

Late last week, San Francisco Medical Examiner Boyd Stephens said he had ruled out pepper spray as a cause of Williams' death because tests failed to find traces of the spray in the soft tissue around Williams' eyes or in his mouth. Stephens said he was concentrating on whether placing Williams in a cramped position contributed to his death.

Tuesday, Stephens also was quoted as saying the autopsy found a high amount of cocaine in Williams' blood, but he said he did not think Williams died of an overdose.

Stephens' comments on pepper spray confused John Crew, a staff lawyer for the American Civil Liberties Union. Crew said, "Our research uncovered that state scientists say no manufacturer of pepper spray -- as of June 1994, at least -- had developed a reliable method of determining trace elements of pepper spray in a body.

"Even if he has a test, it doesn't make sense for the police department's own records to say Mr. Williams was sprayed at least three times and for the medical examiner to conclude there was no evidence of the spray on Williams' face," Crew said. "As we understand it, the officers spraying Mr. Williams were fairly close to him. From the report, we know three officers sprayed him, but we don't know how many times or for how long they sprayed him."

On Sunday, the ACLU called on the state attorney general to adopt an immediate policy barring law enforcement officers from using more than a single one-second burst of spray.

"The manufacturers of pepper spray say that a one-second single burst is what they recommend," said Steve Telliano, a spokesman for the state attorney general's office. "But our office doesn't have the jurisdiction to create such regulations for local law enforcement agencies."